Visiting the world’s vanishing places has become a bit trendy these days—which makes the venerable Earthwatch Institute an unlikely tastemaker. Next year the research organization will bring travelers to what is arguably the most critically endangered site on the planet, then put them to work. Your lab is the lake-stippled tundra of the Mackenzie Mountains and the ridges surrounding Churchill, Manitoba, where permafrost is disappearing first (it’ll likely be gone by 2100) and temperatures are rising fastest (so far, 2ºF). You’ll stay in one of two research stations (watch for grizzlies at one, polar bears at the other), and help Earthwatch researchers monitor the ecosystem. Visitors get around via Inuit sleds and learn to build igloos, but the research itself is high-tech: You’ll use ground-penetrating radar, microclimate data loggers, and soil coring to measure carbon levels in the permafrost. The trip is not all work—there will be time for kayaking and Nordic skiing—but for the most part, you’ll feel more like a researcher than a vacationer.